1. Field of the Invention
The present invention relates to snow gliding skis.
2. Description of Background and Other Information
To be usable on different types of snow, a ski generally has a substantial length, on the one hand, and a variable width, on the other hand, the central zone being generally narrower than the end zones.
When a skier skis on powder snow with skis primarily designed for use on packed snow, he is forced to modify his manner of skiing, especially his body position. An efficient and safe technique requires a forward position, whereby the skier is said to be “engaging the slope”. However, when the skier is on powder snow, he must move his body rearwardly to prevent the front of the skis from digging too much into the snow.
In order to improve their use on powder snow, certain areas of the skis have been proposed to be widened and the length of the shovel, at the front of the ski, has been proposed to be increased, shovel length being defined in the direction of the length of the ski between the front end of the ski and the front contact line, namely, the contact line which the ski would have when placed on a planar, or flat, surface.
The document FR 2 786 108 discloses such a ski in which the front and rear contact lines are closer to the boot than they are in a conventional ski. In addition, the shovel of such ski is significantly raised, the profile of the shovel being made of a succession of portions that all have radii of curvature less than 3 meters (m). The use of such a ski on powder snow is thereby enhanced, although the use of such a ski on packed snow is made much more difficult. Furthermore, in such a ski, the succession of shovel portions, each of which has a radius of curvature that is different but close in value to that of adjacent portions, causes the visual perception of the shovel to be reduced. However, it has been noted that the visual perception of the shovel, i.e., a raised area at the front of the ski, is a psychological factor which inspires confidence in the skier. Indeed, one can understand that the skier will not fear being stopped or destabilized by a low obstacle if he knows that the ski has a raised shovel.
Furthermore, in cases where skis are made flat and then bent to form a shovel, the shovel lacks continuity because it is made by a succession of portions having a straight profile connected together by angular zones. In this case, there is no tangency between the profile of the shovel and the profile of the central portion of the ski, on the one hand, and between the profiles of the various shovel portions, on the other hand. If such a construction were to be considered as having no disadvantage for skis having modestly sized shovels, it becomes a problem in terms of stability and skiability with longer shovels. Furthermore, when a ski has a large shovel made according to the method of bending the front of the ski, the presence of more or less prominent “flat portions” can be noticed. “Flat portions” refers to each portion of the bottom surface whose profile is comparable to a straight line. To detect the presence of “flat portions”, one lays the ski on a planar surface and then lifts the tail of the ski so that the contact point between the bottom surface and the planar surface moves from the front contact line to the end of the ski. This is a rolling movement of the bottom surface on a planar surface. During this rolling movement, as soon as the contact between the bottom surface and the planar surface is no longer a mere transverse line relative to the longitudinal direction of the ski, but a surface, this surface can be regarded as a “flat portion”. The more substantial a “flat portion”, the more it negatively affects the behavior of the ski, particularly the stability of the ski.
Conversely, a ski with no “flat portion” has a better, more stable behavior with more grip. Furthermore, when one skis on powder snow, having a “flat portion” in the area of the shovel can cause the snow to accumulate in the area of this “flat portion”, which can create a blockage.